1. Field of the Invention
The invention relates to a machine and the method for using the machine to apply two-piece connector blocks at specifically defined points on a precise length of multiple conductor cable.
2. Description of the Prior Art
In the electronics industry and computer field, and particularly in the field of minicomputers and microcomputers, it is necessary to utilize multiple lines or busses interconnecting several different elements on the same line as related equipment relys more and more on mass termination technique for interconnections between and among components. For example, it may be necessary to have a sixteen conductor cable for providing a sixteen conductor bus for communicating between a central data processing unit, a peripheral memory, and peripheral data monitoring devices. Such cables may also form a bus providing a coupling between a CPU, an address, a RAM and a ROM. In such use, the conductor cable requires a plurality of intermediate connectors at precise locations along the cable length to connect to elements of equipment in a specific geometric arrangement in the cabinet.
Typically, such a mass termination multiple conductor cable is a flat cable including a plurality of conductors (e.g., sixteen) in a parallel, standardized spaced array in the cable and embedded in or surrounded by flexible plastic insulating material. Also, to minimize the pickup of noise, an electrical shield (typically wire mesh or screen-type conductor) is placed over the insulated array of conductors and an insulating surface coating is applied over the electrical shield. Additionally, above the insulated plurality of conductors and in contact with the electrical shield there is usually positioned a system ground or system common conductor.
For particular assemblies which are produced in substantial quantities, large amounts of multi-conductor cable are required, having a precise length and having two or more connectors disposed at precise locations along each cable length, with at least one connector located at each end of the cable. In a typical application, the various connectors may be of different configurations for interfacing with different types or makes of equipment.
The connector blocks are produced in two mating pieces, and are adapted to be applied with the cable "sandwiched" between the connector half. Each connector has an elongate slot therein, and within the connector are a plurality of spaced apart contacter pins. These pins are spaced apart the same distance that the conductors in the cable are spaced from each other. Also, the first contacter pin is spaced a predetermined distance from one edge of the slot in the connector. When the connector half is properly positioned adjacent the cable, an actuator is operated to press the connector pins through the plastic cable layer and into contact with the individual conductors in the cable. The copper conductor is captured by the pins without shorting other wires. In the cable with which the present invention is adapted to be used, a plurality of connectors, several of which are of differing configurations, must be applied to the cable at precise locations along the cable length, with the proper type of connector being applied at its specified location. A connector may be male or female, and have front or side facing locations.
Prior methods for applying a plurality of connectors to a multi-conductor cable include manual operations. Manual operations are severely labor intensive, wherein the following procedure is currently in common practice.
(a) Cut the multi-conductor cable to length.
(b) Measure and mark locations for each connector along the cable length.
(c) Place one connector half in its proper position.
(d) Place the other connector half in position adjacent the one connector half, with the cable between the connector halfs.
(e) Place the connector halfs and cable in a fixture.
(f) Using an arbor press or a pneumatic press, apply pressure to the connector halfs until they are staked together and the connector pins have penetrated the insulation layer of the cable.
(g) Repeat the last four steps for each connector.
It is apparent that the cost of producing substantial numbers of cable and connector assemblies in this manner can be quite costly in terms of direct labor.
Additionally, it is common that connectors are located in an "up" or "down" position in relation to others on a cable assembly, or that different types of connectors are utilized on the same cable assembly. In the latter circumstances, different fixtures would be required to attach each type of connector to the cable assembly.
In addition, machines are utilized which advance the cable horizontally past a plurality of horizontally disposed stations where the cable is stopped and a connector attached. Such machines do not provide means for reversing the direction of the cable, which precludes the application of a previously applied type of connector at a point further along the length of the cable. In such devices, the catenary effect on the horizontally moving cable may affect the ability to precisely apply the connector at its specific location.
As will be described in greater detail hereinafter, the method and machine of the present invention enable one to precisely apply a plurality of connectors, of any desired type and in any desired array, to a length of multiconductor cable at precise locations along the cable length, and to prepare a plurality of identical cable segments with the same selected connectors mounted at the desired location along the length of each segment.